C/2016 R2 (PANSTARRS)
DEPARTED
Type: Periodic
Perihelion date: 9 May 2018
Perihelion distance (q): 2.6
Aphelion distance (Q) : 1,408
Period (years): 18,733
Eccentricity (e): 1.00
Inclination (i): 58.2
JPL orbit diagram
COBS lightcurve
A 19th magnitude comet was discovered in PanSTARRS 1 images taken with the
1.8m Ritchey-Chretien on 30 August 2016. Early electronic magnitudes put the comet
at 13th magnitude in late December 2016 and brightening quite rapidly. This rate of
brightening did not persist and it scarcely brightened over the next eight months. The
observations are not a good fit to a steady curve, and it seems likely that the comet
has periods of greater activity. It was a couple of magnitudes brighter than the mean
curve in September 2018 and continuted brightening into November even though its
distance from the Sun was increasing. It re-appeared on the PCCP in May/June
2019 as COR8032.
Professional observations in December 2017 suggest that the comet is very rich in
CO, and relatively poor in HCN. It may be quite a large object as it was producing
about a third the amount of CO compared to 1995 O1 (Hale-Bopp) at the same
distance.
Observations (VEMag = visual equivalent magnitude)
Date
10x10 mag
Error
VEmag
Coma '
07-Oct-16
17.15
0.10
14.1
0.2
28-Oct-16
17.15
0.02
14.5
0.2
24-Nov-16
16.49
0.03
13.4
0.4
18-Dec-16
16.52
0.04
13.4
0.5
26-Dec-16
16.53
0.17
13.1
0.3
22-Jan-17
16.54
0.02
13.6
0.5
16-Feb-17
16.64
0.06
13.8
0.5
07-Aug-17
16.05
0.04
13.7
0.6
18-Oct-17
15.11
0.00
12.0
1.1
12-Nov-17
14.99
0.01
11.5
1.5
21-Nov-17
14.65
0.01
11.5
1.8
11-Dec-17
14.42
0.01
11.3
5.2
22-Dec-17
14.24
0.09
11.1
7.1
11-Jan-18
14.56
0.01
11.4
4.0
19-Jan-18
14.25
0.07
11.1
5.8
07-Feb-18
14.38
0.09
11.2
3.3
14-Feb-18
14.75
0.07
11.6
2.8
08-Mar-18
14.90
0.01
11.5
2.6
13-Mar-18
14.90
0.02
11.8
3.2
02-Apr-18
14.93
0.02
11.8
2.3
09-Apr-18
14.75
0.03
11.6
1.8
04-Dec-18
16.01
0.03
12.8
1.1
14-Dec-18
16.08
0.05
13.2
1.0
21-Dec-18
16.21
0.04
14.1
0.7
02-Jan-19
16.28
0.01
13.7
1.0
09-Jan-19
16.25
0.01
13.9
1.1
08-May-19
16.63
0.02
13.8
1.0
24-May-19
16.76
0.04
14.0
0.9
01-Jun-19
16.62
0.07
13.6
1.0
08-Jun-19
16.93
0.03
14.1
0.9
22-Jun-19
17.09
0.03
14.6
1.0
29-Jun-19
17.32
0.06
14.7
0.7
20-Mar-20
19.34
0.07
17.5
0.2
29-Mar-20
19.50
0.05
18.1
0.2